query: SELECT avg(num_of_staff) FROM museum WHERE open_year  <  2009
question: Do Find a number average staffs a-working a museum where was like open 2009.
query_toks: SELECT avg ( num_of_staff ) FROM museum WHERE open_year < 2009
query_toks_no_value: select avg ( num_of_staff ) from museum where open_year < value
question_toks: Do Find a number average staffs a-working a museum where was like open 2009.